Point of use and mini tank heaters
Eemax SPEX35 3.5kW 240V Specifications
Researched from the DOE test procedures, NFPA 54 and NEC code tables, and manufacturer specifications. Updated .
Quick answer
This page collects what is actually published about the Eemax SPEX35 3.5kW 240V and shows what those figures produce, computed rather than transcribed. Anything the listing does not publish is not filled in with an estimate.
Published specifications
Everything here is taken from the listing or the manufacturer, and nothing is inferred.
| Specification | Value |
|---|---|
| Kw | 3.5 |
| Volts | 240 |
Published standard Source: Manufacturer listing data. A specification not listed here is one this listing does not publish. Check the installation manual for the full data plate.
Flow across the temperature rise range
Computed from the published input rating with the energy relation, so these figures cannot disagree with the calculators on this site.
| Temperature rise | Flow | Inlet needed for a 120 F outlet |
|---|---|---|
| 35 F | 0.7 GPM | 85 F |
| 45 F | 0.5 GPM | 75 F |
| 60 F | 0.4 GPM | 60 F |
| 70 F | 0.3 GPM | 50 F |
| 80 F | 0.3 GPM | 40 F |
| 90 F | 0.3 GPM | 30 F |
Published standard Source: Energy relation applied to the published 3.5 kW input at 98 percent efficiency. An electric unit converts essentially all its input to heat, so these figures track the manufacturer curve more closely than a gas unit does.
What circuit it needs
At 3.5 kW and 240 volts this draws 14.6 amps. NEC 422.13 treats it as a continuous load, so the circuit is sized at 125 percent, giving 18.2 amps of design load.
That means a 20 amp double pole breaker and 12 AWG copper. Confirm the circuit count against the installation manual, and see the breaker and wire page for 3.5 kW, the nearest rating worked through in full.
How it sits against the rest of its category
Other point of use and mini tank heaters in this catalog: Eemax SPEX55 5.5kW 240V, Eemax EEM12004 4kW, Stiebel Eltron DHX 12-2 Trend 12kW, Stiebel Eltron DHC-E 8/10.
Compare them on input rating and on the figures the manufacturer actually publishes rather than on the headline number in the listing title, which in this category is frequently a maximum measured under conditions the listing never states.
Other point of use and mini tank heaters
Eemax SPEX55 5.5kW 240V
$247.61At 5.5 kilowatts this reaches a usable flow for a utility sink rather than just a basin.
Best for: A utility or laundry sink
Check price on Amazon
Eemax EEM12004 4kW
$155.98A four kilowatt point of use unit at the budget end of a brand that sells mostly into commercial washrooms.
Best for: A single basin
Check price on Amazon
Stiebel Eltron DHX 12-2 Trend 12kW
$266.14Twelve kilowatts at the point of use is enough for a shower, which puts this in a different category from every mini tank on this page.
Best for: A remote shower with its own circuit
Check price on AmazonFrequently asked questions
- What are the specifications of the Eemax SPEX35 3.5kW 240V?
- The listing publishes kw, volts and related figures, shown in full in the table on this page. Anything not shown is something the listing does not publish, and this page does not estimate it.
- What circuit does the Eemax SPEX35 3.5kW 240V need?
- It draws 14.6 amps at 240 volts, which becomes 18.2 amps of design load under the NEC continuous load rule. That means a 20 amp double pole breaker with 12 AWG copper. Confirm against the installation manual.
- Is this page based on hands-on testing?
- No, and we never claim otherwise. Everything here is compiled from the manufacturer listing, published specifications and the energy relations that turn those specifications into flow and recovery figures. We do not test products in person. Where a figure is not published, this page says so rather than estimating it.
- Are the prices on this page current?
- They come from verified catalog data at the time the page was built, and prices in this category move often. Treat any price shown as a guide and check the listing itself before deciding. Availability moves even faster than price does on water heater accessories in particular.
Turn the breaker off before touching an element. Both legs of a 240 volt circuit are live, so switching one of them off is not enough, and testing with a meter before you touch anything is the habit that matters. Never energise an element that is not submerged: dry firing destroys an element in seconds and can crack the tank lining around it.